Long Position
A long position means you've bought a currency pair expecting it to rise in value. If you go long EUR/USD at 1.0800, you profit when the price goes up. Each pip of upward movement adds to your profit; each pip downward adds to your loss. The amount per pip depends on your position size.
Going long is what most people think of when they think of trading — buy low, sell high. In forex, the mechanics are straightforward: you click "buy," and your broker opens a position at the current ask price. To close the trade, you sell at the current bid price. If the bid is higher than the ask you paid, you profit.
While going long feels intuitive, it's no more or less valid than shorting. Currencies move down just as readily as they move up. Some of the best trading opportunities come on the short side, especially during risk-off events when "safe haven" currencies like USD, JPY, and CHF tend to strengthen against riskier currencies.